NEW YORK — David Cassidy, the teen and pre-teen idol who starred in the 1970s sitcom The Partridge Family and sold millions of records as the musical group’s lead singer, died Tuesday at age 67.

Cassidy, who announced earlier this year that he had been diagnosed with dementia, died surrounded by his family, a family statement released by publicist JoAnn Geffen said. No further details were immediately available, but Geffen said Saturday that Cassidy was in a Fort Lauderdale, Fla., hospital suffering from organ failure.

“David died surrounded by those he loved, with joy in his heart and free from the pain that had gripped him for so long,” the statement said. “Thank you for the abundance and support you have shown him these many years.”

The Partridge Family aired from 1970-74 and was a fictional variation of the ’60s performers the Cowsills, intended at first as a vehicle for Shirley Jones, the Oscar-winning actress and Cassidy’s stepmother. Jones played Shirley Partridge, a widow with five children with whom she forms a popular act that travels on a psychedelic bus. The cast also featured Cassidy as eldest son and family heartthrob Keith Partridge; Susan Dey, later of L.A. Law fame, as sibling Laurie Partridge; and Danny Bonaduce as sibling Danny Partridge.

It was an era for singing families, like the Osmonds and the Jacksons. The Partridge Family never cracked the top 10 in TV ratings, but the recordings under their name, mostly featuring Cassidy, Jones and session players, produced real-life musical hits and made Cassidy a real-life musical superstar.

The Partridges’ best known song, “I Think I Love You,” spent three weeks on top of the Billboard chart at a time when other hit singles included James Taylor’s “Fire and Rain” and Smokey Robinson and the Miracles’ “The Tears of a Clown.” The group also reached the top 10 with “I’ll Meet You Halfway” and “Doesn’t Somebody Want to be Wanted,” and Cassidy had a solo hit with “Cherish.”

Cassidy’s appeal faded after the show went off the air, although he continued to tour, record and act over the next 40 years, his albums including Romance and Didn’t You Used To Be? He made occasional stage and television appearances, including an Emmy-nominated performance on Police Story.

Meanwhile, The Partridge Family remained popular in reruns and Cassidy, who kept his dark bangs and boyish appearance well into middle age, frequently turned up for reunions and spoke often about his early success.

“So many people come up to me and talk to me about the impact it [the show] had,” he told Arsenio Hall in 1990.